NO. 2297. BRACEIOPOD GEA-US PLATYSTROPHlA—AlcEWAN. 441 



Figs. 9-13. Platystrophia amoena longicardinalis, new variety, p. 412. 

 9. Pedicle valve. The figure shows the shallow sinus. 



10. Brachial valve. The low spreading fold is typical. 

 Trenton limestone, Trenton Falls, New York. 



11, 12. Brachial valves. 



13. Cardinal view showing the ventricosity. All the specimens show the char- 



acteristic acuminate liinge extremities, 

 Trenton group (Prosser limestone), Fountain, Minnesota. 

 Figs. 14-17. Platystrophia ainoena rohusta, new variety, p. 412. 



14. Cardinal view. The plump form is characteristic. 



15. Pedicle valve. The shallow sinus is illustrated. 



16. Anterior view. Tlie figure illustrates the shallow sinus. 



17. Bracliial valve showing the characteristic strong growth lines. 

 Trenton limestone, Trenton Falls, New York. 



Figs. 18-22. Platystrophia globosa, new species, p. 413. 



18. Pedicle valve. The triplicate plication pattern is well shown. 



19. Cardinal view. The plump form is typical. 



20. Anterior view shoAving the broad sinus. 



21. Brachial valve illustrating the broad low fold. 

 Trenton group, Nashville, Tennessee. 



22. Brachial valve. 



Trenton limestone, Ellisburg, New York. 

 Figs. 23-26. Platystrophia strigosa, new species, p. 417. 



23. Anterior view showing the typical thin form, low fold and shallow sinus. 



24. Pedicle valve. The broad sharp plications are characteristic. 



25. Brachial valve, of a mutation with five plications on the fold. 



26. Brachial valve of a somewhat larger specimen. 

 Maysville group (Fau-mount), Newport, Kentucky. 



Figs. 27-29. Platystrophia corryvillensis, new species, p. 419. 



27. Cardinal view showing the ventricose brachial valve and long hinge line. 



28. Brachial valve. The fold scarcely rises aliove the general convexity of the 



valves. 



29. Pedicle valve. The broad sinus is typical. 

 Maysville group (Corry\ille beds), Cincinnati, Ohio. 



Figs. 30-35. Platystrophia morroivcnsis (James), p. 418. 



30. Lateral view. The globose form is characteristic. 



31. Pedicle valve showing the low spreading fold. 



32. Cardinal view. The short hinge line is characteristic. 



33. Pedicle valve of an indiAddual with three plications in the sinus. 

 Maysville group (Corry^dlle beds). Morrow, Cincinnati, etc., Ohio. 



34. Pedicle valve of a longer hinged individual. 



35. Brachial valve of a very short hinged specimen, 

 Maysville group (Corryville beds), Cincinnati, Ohio. 



Figs. 36-41. Platystrophia juvenis, new species, p. 416. 



36. Brachial valve of a typical specimen. 



37. Brachial valve of a mutation with seven plications on the lateral slopes. 



38. Pedicle valve of a mutation which approaches Platystrophia pauciplicata. 



39. Pedicle valve of a typical specimen. 



40. Anterior view showing the even convexity of the valves. 



41. A group attached to a bryozoan frond. 



Maysville group (Fairmount beds), Newport and Covington, Kentucky. 

 Figs. 42-43. Platystrophia nitida, new species, p. 418. 



42. Brachial valve showing the characteristic low spreading fold. 



43. Cardinal view. The short hinge line is characteristic. 

 Maysville group (Fairmount), Cincinnati, Ohio. 



